Nasty Gal

BlueBridge Digital

iCracked

Asana

OrgSync

HireVue

GitHub

BandPage

Lark Technologies

Uptown Cheapskate

Spartz Media

SeatGeek

Evatran

Solomon Group

MinoMonsters

Orbotix

Arvixe

Mutual Mobile

LaunchKey

MAZ Digital

ZenPayroll

The Adoni Group

Video Blocks

Course Hero

Marketing Zen

Wireless Communications

Leap Motion

Luke's Lobster

Yodle

Think Impact

On this year’s 30 Under 30 list, you’ll find inventors, fashionistas, job creators, work-place innovators, serial entrepreneurs, and more than one honoree who started a business in middle school. Collectively, they make more money, employ more people, and have raised more capital than any previous 30 Under 30 list. Prepare to be awed!

--Donna Fenn

Sophia Amoruso started auctioning vintage clothing items on eBay in 2006, but ultimately found that the online marketplace cramped her style. When she launched her own website and branched out beyond vintage, young women flocked to her confidently sexy brand, Nasty Gal, and made it a cult sensation. With 269 full time employees, $49 million in venture capital, and a reported $100 in revenues, the company shows no signs of slowing down.

Santiago Jaramillo (right) describes entrepreneurship as “a sickness I was born with.” The Columbia-born founder started his career in business as a boy, delivering water to his neighbors in a red Radio Flyer wagon. His latest venture, BlueBridge Digital, sells customizable mobile apps into three vertical markets: tourism, higher education, and religious organizations. Unlike competitors, he uses a subscription-based business model.

A.J. Forsythe (left) and Anthony Martin (right) don’t want you to stress over your cracked iPhone screen. Their company, iCracked, designs repair kits for common iPod, iPhone, and iPads damages, has them manufactured cheaply in China, and then sells them to users--either directly for about $65, or through licensed independent repairmen known as iTechs, who visit users and repair their devices.

Facebook alums Justin Rosenstein (left) and Dustin Moskovitz (right) count some of the country’s fastest-growing start-ups among the faithful users of their task management software. Pinterest, Dropbox, Foursquare, Airbnb, Stripe, and Uber all use cloud-based Asana, which was originally developed within Facebook. Asana increases workplace productivity by allowing teams to create, collaborate on, and track tasks across an organization.

Eric Fortenberry’s OrgSync is an online platform that enables universities and student organizations to communicate with and efficiently organize their members. Student leaders can manage a group's budget, post events, track member involvement, and send out group messages, among other functions. The company has two million registered users across 40,000 member organizations on 350 college campuses worldwide.

If HireVue’s Mark Newman has his way, the resume may become a thing of the past. His platform enables job candidates to put their best face forward by answering employers’ questions via webcam. The videos are then stored and viewed by prospective employers, who can compare and share them, making it easier and faster to find the right employee. HireVue is growing so quickly that Newman is using his own platform to staff up.

P.J. Hyett (left) and Chris Wanstrath (right) built GitHub, a portal that lets Web developers collaborate on each other's coding projects. Uploading open-source code for the public is free, but enterprise clients such as Microsoft, Walmart, and Lockheed Martin pay GitHub to keep their code out of public view, sharing it only among their own teams. The result: 300 percent year-over-year growth and a whopping $100 million in Series A funding from Andreessen Horowitz.

J. Sider started Bandpage in 2009 as a Facebook app where musicians could give fans updates, tour dates, and photos. Since then, the company has evolved into a platform that helps bands create stand alone websites, while offering more tools for drawing in fans. Bandpage’s latest feature, Experiences, lets fans pay for access to band perks, such as a $50 bowling game with Philadelphia indie band Free Energy or $2,500 to Skype with Ozzy Osbourne's guitarist.

Julia Hu’s (left, pictured with her team) Lark Technologies makes health monitors that sync with wearers’ smartphones to provide real time data and coaching on sleep patterns, nutrition, and exercise. Products such as Lark Life and Lark Pro might tell you, for instance, your optimal bedtime, or when you should go take a run. Data on the company’s thousands of users is also helping Hu create the world’s largest sleep database.

Chelsea Sloan and her brother, Scott, grew up in a family of entrepreneurs. Their parents own a chain of shops that sells gently used children’s clothing. In 2009, the siblings teamed up to launch Uptown Cheapskate, which sells used and overstock apparel that appeals to teens and twenty-somethings. The company is now a franchise of 25 stores in 13 states; the founders plan to double that number this year and are tracking for $17 million in revenue.

Emerson (left) and Gaby Spartz (right) each built their first websites at age 12. Today, Spartz Media is home to 12 web properties, including the highly popular Harry Potter fan site, MuggleNet, which earned Emerson Spartz an exclusive interview with J.K. Rowling. MuggleNet, and other sites such as DailyCute, OMG Facts, and Smartphoned, rack up 160 million monthly page views.

Russ D’Souza (left) and Jack Groetzinger (right) describe SeatGeek as “like Kayak, but for events tickets.” The platform aggregates tickets from more than 50 other sites, such as StubHub and Ticketmaster, allowing customers to score the best seats at the most economical price. The company just inked a lucrative partnership with Yahoo! Sports.

Rebecca Hough teamed up with her father, Tom Hough, and leveraged his expertise with electrical transformers to create Plugless Power, a system that wirelessly charges your electric vehicle. Her company, Evatran, is working with major U.S. and German auto manufacturers on an OEM product, but has already rolled out an aftermarket product for owners of Nissan Leaf and Chevy Volt.

Gary Solomon was an NYU theater and lighting design student who, eager to make his mark in his hometown, ditched the Big Apple for the Big Easy. Since then, his live event and multimedia installation production company, Solomon Group, has designed an interactive submarine installation for the New Orleans World War II museum, installed a dramatic lighting system at the Superdome, and built the broadcast sets for CBS at this year's Super Bowl.

Josh Buckley’s MinoMonsters is one of the top 100 grossing apps in the U.S. Three million kids play MinoMonsters, collecting teams of colorful monsters and taking them into battles. The youngest Y Combinator alum, UK-born Buckley is now set on breaking free of the gaming world into the lucrative land of licensing--games, toys, books, even movies. Think Disney and Rovio.

Techstars alums Ian Bernstein (left) and Adam Wilson (right), who shared a passion for robots, founded Orbotix and built Sphero – a tennis-ball shaped robot that can be controlled with your smartphone. An expensive dog toy? More like the beginning stages of physical meets virtual world. With $7 million in funding and another $7 million on the way, the founders are working on new sophisticated robots that can be controlled remotely.

Arvand Sabetian (not pictured) started Arvixe, a web hosting company, after his junior year in high school. Since then, the company has grown to $8 million in revenue and 85 employees (pictured), and has been on the Inc. 500 list for the past two years. And here’s the kicker: the company is completely virtual, with all employees working remotely. Sabetian uses software and a complicated points system to makes sure his staff is delivering 24/7 white glove customer service.

John Arrow (second to left), Tarun Nimmagadda (not pictured), Jason Story (left), Sam Gaddis (right), and Mickey Ristroph (second to right) started their company, Mutual Mobile, with a gimmicky app that calculated the free-fall time of an iPhone tossed in the air. But a big shift to the B2B space catapulted the bootstrapped company to $26 million in revenue, with enterprise clients in the healthcare, education, and retail industries.

Geoff Sanders (right), Yo Sub Kwon (center), and Devin Egan (left) want their new company, LaunchKey, to become the standard for passwordless authentication. Their smartphone app thwarts hackers by letting users sign into a site with a username alone. The software sends a signal to the user’s smartphone and he or she completes the sign-in by swiping the smartphone screen. The app is available free in the Apple App Store, with an Android version coming soon. And on May 31, LaunchKey’s API will be made public.

Paul Canetti (left) and Simon Baumer (right) are making it easier for print publishers to create content for tablets and smartphones. Their DIY platform, MAZ, allows publishers (such as Inc.) to create an app, distribute it, and receive reporting and analytics on the app’s performance. Since the company’s launch in April 2011, about 100 publishers from 26 countries have signed on. In the future, the founders hope to take the app to the consumer market.

Tomer London’s goal is to “delight” small business owners with his payroll processing and accounting software-as-a-service platform, ZenPayroll. For a fraction of the price much larger competitors charge, customers can be up and running in minutes, using a template system based on simple questions that predict the kind of payroll and accounting features they’ll need. It's also paperless, making automatic deductions and payments for state and federal taxes, and giving employees access to their account information.

Jordan (right) and Jensen Adoni (left) are on a mission to bring shoe manufacturing back to the U.S. The Adoni Group’s factory is based in Manhattan and produces 220 pairs of bespoke and off-the-rack shoes a day, including the GiraffeWalk leather flats that Beyonce wore in Cuba. The company also acquired the iconic skate boot manufacturer, Klingbeil, saving the troubled company from extinction.

Joel Holland’s Video Blocks is disrupting the stock footage industry. The company is an online marketplace where videographers upload content that customers can then access for a monthly subscription of $79. The Netflix-like pricing model has allowed Video Blocks to reach a mass market of schools, churches and amateur video enthusiasts in addition to professional filmmakers. Customers currently download some 25,000 clips a day, for a total of nearly 9.4 million clips since 2011.

Students at 4,500 schools use Course Hero to access other college students’ notes, study guides, class notes, past course exams, flash cards, live tutoring services, and supplementary courses. Andrew Grauer, who founded the company with his twin brother, David, and Gregor Carrigan, came up with the idea as a sophomore at Cornell University, when he was laid up with a knee injury and had trouble getting to class. The site now hosts more than 7 million documents and is on track for $10 million in revenue this year.

Shama Kabani founded Marketing Zen Group in 2009, back when few companies knew they should care about investing in social media. Widely recognized as a trailblazer in the field of digital marketing and public relations, Kabani now has a virtual staff of 30 and clients such as Haggar Clothing and the Dallas YMCA. She also wrote The Zen of Social Media Marketing, which was one of the first comprehensive best-selling guides on the market.

Krish Patel, who worked for Verizon during college, began planning to open his first Verizon Wireless store around graduation time. Five years later, he operates 40 stores in four states and has 300 employees. He’s planning to hit 100 stores in the next five years and is predicting $55 million in revenue this year.

Imagine being able to virtually reach into your computer and manipulate objects. David Holz (left) and Michael Buckwald (right) have made that possible with Leap software. Install it on your computer and a compact controller with infrared cameras lets you use your hands to play games, move objects, draw, paint, browse the web -- just as you would in the real world. The product is brand new to the market; future applications may include mobile and medical devices and cars.

Luke Holden (right) and Ben Conniff (left) are bringing the Maine lobster shack aesthetic to New York City, Philadelphia, and Washington DC. Their 11 restaurants, all situated in small, simple spaces to keep overhead down, serve up lobster rolls, crab rolls, and other sea fare. Financed almost entirely with cash flow, the company did $8.5 million in revenue last year.

Ben Rubenstein (right), Nathaniel Stevens (nor pictured), and John Berkowitz (left) started Yodle to help small businesses transition from offline to online marketing channels. Yodle connects consumers to over 30,000 local businesses through desktop and mobile websites, SEO, and paid search advertising campaigns. The largest company on our list this year, Yodle racked up $130 million in revenue last year and has more than 950 employees.

Saul Garlick’s (left) Think Impact attempts to solve the world’s most pressing problems by gathering students, corporations, conference communities, and enterprise incubators in Ghana, Kenya, Rwanda and South Africa. Along with local innovators, the groups prototype products and services such as a rainwater catch system and process for cleaner charcoal using maze. ThinkImpact also offers training and events that help university faculty develop experiential education in social entrepreneurship.